Phonograph machine



Dec lz; 19.33. R. F. MALLINA" PHONOGRAPH MACHINE I Filed Jan. 28. 1931 3 Sheets-Sheet 1 INVENTOR R. F: MALL/NA ATTORNEY 1933- R. F. MALLINA 1,938,706

PIHONOGRAPH MACHINE Filed Ja 28. 1931 3 Sheets-Sheet 2 0 4 W 9 SP 3 R 6 l/VVENTOR R. E MALL INA ATTORNEY 12, 1933. R. F. MALLJNA 1,933,706.

PHONOGRAPH smegma Filed Jan. 28. 1931 s Sheets -Sheet s INVENTOR R. F MALL/NA BY ATTORMS'Y Patented ca. 12,1933 I 1,938,706

UNITED. STATES PATENT OFFICE PHONOGRAPH MACHINE Rudolph F. Mallina, New York, N. Y., assignorto Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York I Application January 28, 1931. Serial No. 511,789

Claims. (Cl. 274-) This invention relates to sound reproducing every quarter revolution. A lever mechanism is machines and more particularly to machines 01 provided for raising and lowering the reprothis kind which are suitable for call announcducers simultaneously, as for instance when it mg in telephone systems. is necessary to change the record and'faulty op- 53 In telephone exchange areas including both eration due to slight variations in the lateral automatically and manually operated central position of the reproducers as they are lowered ofllces, when a call is made from an automatic into contact with the record is prevented by proto a manual ofiice, some convenient means must viding a group of' concentric grooves instead of be provided for translating the dial impulses ,a single concentric groove for each pronounce- 10 into a form which can be readily understood by ment. In this way a reproducer may come in the manual operator who is to complete the contact with a groove on either side of the groove connection to the called line. This means may intended without causing faulty operation of the take the form of sound reproducing apparatus machine. Due to the extremely low impedance actuated by relays controlled by the dialed imof the reproducers and to the comparatively hard 15 pulses, selectively to reproduce recorded num material used in the record, a record may be bers so that the manual operator hears the desused for several days of Continuous Operation ignation of the called line just as she would if the fore being replaced call had originated in a manual oiiice. One form A feature which contributes to the steady opof such reproducing apparatus comprising a film eration of this machine is a novel thrust bearing 20 record of the digits and letters used in line for the turntable by means of which the turntable designations, optical means for reproducing the may be driven from below through a suitable record, and the necessary associated circuits is vibration filter without the use of a stufiin bOX shown in Patent 1,645,573 toBascom, October 18, to retain the oil in the bearing.

1927. w Further features of the invention are the re- 25 it is the object of this invention to provide m v le turntable for facilita ing the ch n i so phonographic apparatus for call announcing pur- 0f for Clamping and centering poses which is very compact, relatively cheap, the record on the turntable and contacts operand so reliable in its operation that it will give d y t r tat n of th turnta f c nsatisfactory service without attention of any tr l th p r n f lay in th u p h- 30 kind for considerable periods of time. 4 cult and for giving an alarm if the machine fails In accordance with the general features of this to function in the manner intended. invention, the announcing machine is provided These and other features of the invention will with a motor driven turntable which carries a b m re l rly und rst d fr m th foll win record of all the digits and letters used in the line .de description and the accompanying drawii designation to be repeated. Individual reproingsin which:

ducers, one for each letter and digit are all Figs. 2 d 3 e a front View, a d w and normally in contact with their respective grooves 11 plan r sp tiv f the p r d structur so that all of the recorded signals are repeatedly 0f t e Call announcing machine, accordin to this reproduced and transmitted to an external invention; 7

-0 selector circuit associated with the telephone F 4 S a detail V ew f th turntable and system. record showing particularly the manner in which An important feature of the invention is the the record s mp d t t tu ta Fi 4--A general arrangement of the parts of the machine 15 8- S B- V w Of the Parts Of F 4 in S- for the purpose of preventing any vibrations, Sembied relation;

45 such 3,5 gear vibrations from the driving motor, Fig. 5 is an enlarged sectional VlGW 01 the thrust from reaching the turntable. This general 'arbearing for t turntable; rangement consists of vibration damping mate Fig. 6 is a detail view of the linka m S- rial between the various parts of the machine ing and lowering the reproducers; and 'frame, a flywheel on the turntable shaft, and Fig. 7 is a detail of the interrupter and alarm 50 specially proportioned mechanical filters in both contacts operated by the turntable. 5

the motor and turntable shafts. The machine Referring now particularly to Figs. 1, 2 and 3, is kept very compact by using a record of only the constant speed motor 10 drives the main shaft moderate size and choosing such small repro- 11 through the mechanical filter coupling 12 and ducers that they may be arranged in four groups the worm gear 13. The shaft 11 carries a fly- 55 above the record to give a pronouncement for wheel 14 of the necessary mass to prevent ir- 1 g J regularitiesinspeedmchasthoseduetounavoidable imperfections in {the cutting of the teeth of the worm gear drive, and terminates in a flange 15 of a second mechanical filter 16. In order that these filters may successfully eliminate all undesired vibrations, it is essential that they be critically damped with respect to torsional vibrations as well as those of a vertical nature andalsothattheybesuchthataslightmisalignment of the shafts will not cause disturbances at the turntable. One construction which has been found very satisfactory for this purpose consists of a plurality of layers of felt cemented together and forming the sole driving connection between the parts thereby connected. The coupling may be covered by a wood fibre or metal casing 66 which is preferably secured to the upper flange l9 and free to rotate with respect to flange 15. In order to prevent possible injury to the fllter in case'of a too great torsional deflection, a stop member 17 secured to the casin 66 engages the pin 18 on the flange 15 if the filter is deflected too far in either direction. A similar arrangement is also provided for the fllter 12.

Securedtothetopflange 19isthe flange 20, Fig.5,ofthethrustbearing21. Thisflangealso serves as a closure for the casing 22 which is substantially fllled with 011. Threaded into the,

flange 20 is the turntable shaft 23 which is supported by thethrust ring 24 carried by the lateral bearing 25 which is supported by the top plate 26 of the machine. The main shaft 11, which, as already stated, is driven by the motor 10, transmits its power through the felt layers of the coupling fllter 16 to the top flange 19 and through the flange 20 to the shaft 23. As will be clearly seen from Fig. 5, the casing 22 rotates withthe flange 20 andthe shaft 23 and maintains aheadofoil.onthethrustsurfaceofthering24 aswellasonthelateralsurfacesil'lofthe bearing 25. Due to this arrangement it is possible to drive the shaft from below without the use of the conventional stufllng box to prevent the escape of oil from the thrust bearing.

As a further precaution against the transmission to the turntable of undesired vibrations, the motor 10 is mechanically insulated from the bottomplatemibyalayerof felt 29andasimilar layer of felt 30 is interposed between the top plate 26'and the side walls 31 of the machine casing. The cover 33 of the machine is made dust-proof by means of a gasket 33 and the operation of the machine may be observed through the shatterproof glass 34 without raising the cover.

The material of the record 35, Fig. 4, must be such that the record will give continuous reproduction comparatively free from surface noise for a considerable period of time. A pressing of cellulou acetate has been found quite satisfactory from this standpoint. The grooves of the record are all concentric and are arranged in sixteen groups of six grooves each. Only fourteen of these groups are required for the call designations which are 1, 2, 3, 4, 5. 6, 7, 8, 9, 0, J, M, R. andWandarelocatedasshowninFig.4. The other two groups shown are blank grooves and serve no useful purpose in the present machine but reproducers are provided for them to give a symmetrical appearance to the reproducer arrangement. It should be noted, however, that these spare grooves might be used to advantage as for instance for recording signals which would perform the function of the interrupter and alarm contacts described below. All the grooves of each of the groups used have recorded in them the same digit or letter of the call designation, the recording being arranged to give four pronouncements per revolution with the necessary silent intervals between them for the operation of the telephone relays as will be more fully described. The record is preferably in annular form and contains a deep concentric groove 36, which corresponds to a groove cut into the master record when it is being made, and serves to center the record accurately on the removable turntable 37. The clamping member 38 is attached to the turntable 3'? by a threaded connection 87 as indicated and the ring 39 engages the groove 36 to hold the record tightly in engagement with the turntable as well as to center it accurately thereon. The peripheral clamping ring 40 engages pins 41 on the turntable and holds the periphery of the record tightly in engagement with it. The record is keyed to the turntable by pin 42 and the turntable is also keyed to its supporting member a 84 by a pin 77 on the member engaging a hole '78 in the turntable so that the pronouncements will occur in the correct time relation to the operation of the interrupter contact to be described below.

The reproducers 43, only one of which is shown in Fig. 3, are attached to the reproducer arms 44 by a plug and socket connection and may be clamped in place by the thumb screws 45. These arms are pivoted to the supporting brackets 48 by shafts 47 and the group of four reproducers is suitably counter-balanced by one or more weights 48 so that the reproducers engage the record with the proper bearing pressure. For convenience in changing the record there is pro 'vided a reproducer lifting mechanism which is shown more clearly in Fig. 6. A ring 49 surrounds the thrust bearing supporting member 50 of Fig. 5 and has attached thereto members 51 connecting. at their other ends to the bell cranks 52 which turn about their pivots 53 to raise or lower the bars 54 supporting the groups of reproducers.

The ring 49 is turned to raise or lower the reproducers by the crank 55 which is pivoted in the bearing 56 and terminates in a socket 57 threaded internally .to engage the screw 58. If the crank 55 is rotated with a clockwise motion, the screw 58willbedrawntotherightandthecrank59 will be rotated to move the connecting bar 60 to the left thereby imparting a clockwise rotation to the ring 49 and to the connecting linkages already described. This motion will cause the bellcranks52toberotatedina clockwisedirection thereby raising the reproducers out of contact with the record. Similarly, by a reverse movement of the crank 55, the reproducers may be lowered into contact with the record grooves in a very gradual manner so that no injury to the grooves or reproducers is thereby sustained. As already pointed out, there is a reproducer for each digit and letter of the call designation and since each digit and letter is recorded in a number of grooves, any slightlateral displacement of the reproducers will not cause them to contact with a groove containing a designation other than the one intended.

It has been found preferable to use records of thehill and dale type and the reproducers 43 are preferably of the general type disclosed in an application of A. C. Keller, Serial No. 402,138, filed October 24, 1929. Reproducers of this type are particularly suitable for this purpose in thatv to the telephone system. Multiple connections arealsorunfromterminals 61tothetestiacks82 on the front of the machine whereby the opera-- tion of any given reproducer maybe quickly tested by means of earphones.

The turntable supporting member 64 which is I keyed to the shaft 23 by pins 79 and 80 (Fig.

and upon which the removable turntable 37 is placed has four cam surfaces 65 on its periphery midway between the positions of the pronounce-- ments on the record 35. Cooperating with the periphery of the member 64 at 90 intervals are cam followers such as 69 of Fig. 7 secured to the main spring '70 of the interrupter 76. The main spring carries a feather spring 71 which has a forward alarm contact 72 and a back speech contact 73. In each of the four positions this structure is used to provide two alarm and two speech contacts one above the other which operate simultaneously. The assembled interrupters are secured to the top plate 26 by screws 74, '74 and may be adjusted laterally to the correct po-.

sition by screws 75. While the cam followers are in contact with the curved portions of the periphery, that is during the speech intervals, the main springs '70 will be deflected so that the speech contacts will be closed and the alarm contacts open but when a flat cam surface 65 comes into position the spring 70 will return to particular circuits for accomplishing this result form nopart of the present invention and hence need not be described but one arrangement for this purpose is fully disclosed in the Bascom patent referred to above. The alarm contacts may be usedinvarious waysasacheckontheoperation of the machine; for example, they may be arranged to send a current through the reproducer windings during the. silent intervals as a test *0! their continuity so that if one of them should cease functioning by reason of an open circuit, this fact would be indicated by the operation of an alarm signal.

What-is claimed is:

1. In a phonograph machine the combination with a turntable carrying a record containing a plurality of groups of concentric grooves, and a reproducer engaging one of the grooves of each group, of contacts operated by the rotation at the turntable for controlling the effectiveness of the reproducers.

2. In a phonograph machine the combinati with a turntable, driving means therefor, a cam rotated by said driving means and contacts operated by the cam, of a record on the turntable containing a plurality of groups of concentric grooves and a reproducer engaging one of the grooves of each group and electrically'connected to the contacts.

3. In a phonograph machine the combination with a turntable carrying a record containing a plurality of groups of concentric grooves, driving means therefor and a plurality of reproducers disposed in groups around the record, of a driven member comprising a cam for each group of reproducers and contacts operated by the cams and electrically connected to the reproducers.

4. In a phonograph machine the combination with a record within a dust-proof casing and driving means therefor of a plurality of groups of reproducers engaging "the record and means operable externally of the casing for simultaneously raising and lowering all the reproducers.

5. In a phonograph machine a shaft carrying 

